#pragma once
#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
typedef int Mt;
typedef struct DList
{
	Mt val;
	struct DList* fro;
	struct DList* def;
}DL;
DL* DLinit();
void DLpushback(DL* head,Mt x);
void DLprint(DL* head);
void DLpopback(DL* head);
void DLpushfront(DL* head,Mt x);
void DLpopfront(DL* head);
DL* DLfind(DL* head,Mt x);
void DLerase(DL* head, DL* ptr);
void DLInsert(DL* head,DL * ptr);